Linux Learning Commands Summary ⑩⑥

#ifconfig命令: used to view and configure network devices

Displays information about the network interface for the current activation state:

 [[Email protected]_168_102_centos ~]# ifconfigeth0 Link encap:ethernet hwadd  R  00:16:3e:e2:7b:d2 inet addr:  10.221.168.102 bcast:10.221.171.255  Mask:255.255.252.0 Inet6 addr:fe80::  216:3eff:fee2:7bd2/64 Scope:link up broadcast RUNNING multicast MTU:  metric:1 RX packets:  3689339 errors:0 dropped:0 overruns:0 frame:0 TX packets:1724548 errors:0 dropped:0 overruns:0 carrier:0 collisions:  0 txqueuelen:10 00 RX bytes:  370517889 (353.3 MiB) TX bytes:211155888 (201.3 MiB) Interrupt:  163 simple description:  

Eth0: Network interface

Link encap: Network type

HWADDR: Network card Physical Address (MAC address)

Inet ADDR:IP Address

Bcast: Broadcast Address

Mask: Subnet Mask

Up: Represents the network card is on; RUNNING: Network cable that represents the NIC is connected; broadcast: Supports point-to-point communication protocol; multicast: Support multicast

    MTU: The maximum transmission unit of the NIC

RX Packets: Number of packets received

TX Packets: Number of packets transmitted

RX byte: The exact number received

TX byte: The exact number of transmissions

Interrupt: Terminal information

Lo        Link encap:local Loopback            inet addr:127.0.0.1  mask:255.0.0.0          inet6 addr::: 1/128 Scope : Host up          LOOPBACK RUNNING  MTU:16436  metric:1          RX packets:errors:0 dropped:0 overruns:0 frame:0          TX packets:errors:0 dropped:0 overruns:0 carrier:0          collisions: 0 txqueuelen:0           RX bytes:1568 (1.5 KiB)  TX bytes:1568 (1.5 KiB)

Lo: Local Loop interface

Displays the specified network interface:

[Email protected]_168_102_centos ~]# ifconfig eth0eth0      Link encap:ethernet  00:16: 3e:e2:7b:d2            inet addr:10.221.168.102  bcast:10.221.171.255  mask:255.255.252.0          inet6 addr:fe80::216:3eff:fee2:7bd2/64 scope:link up          Broadcast RUNNING multicast  MTU:  metric:1          RX packets:3694095 errors:0 dropped:0 overruns:0 frame:0          TX packets:1725551 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:1000           RX bytes:370998440 (353.8 MiB)  TX bytes:211382468 (201.5 MiB)          Interrupt:163

Configure the IP address (effective immediately, but not permanently):

Ifconfig eth0 192.168.122.22

Configure IP to eth0 NIC: 192.168.120.56

Ifconfig eth0 192.168.122.22 netmask 255.255.255.0 (or 192.168.122.22/24)

Configure IP address for eth0 NIC: 192.168.120.56, plus child mask: 255.255.255.0

To start/close the specified network interface:

Ifconfig eth0 on

Ifconfig eth0 Down

Set the maximum transmission unit:

[[email protected] ~]# ifconfig eth0 MTU 1480[[Email protected]~]# ifconfig eth0 eth0 Link encap:ethernet HWaddr00:0c:29:44:b7:60inet Addr:192.168.108.128 bcast:192.168.108.255 mask:255.255.255.0Inet6 addr:fe80::20c:29ff:fe44:b760/64scope:link up broadcast RUNNING multicast MTU:1480 Metric:1RX Packets:373 errors:0 dropped:0 overruns:0 frame:0TX Packets:275 errors:0 dropped:0 overruns:0 carrier:0Collisions:0 txqueuelen:1000RX Bytes:37682 (36.7 KiB) TX bytes:35735 (34.8KiB) [[Email protected]~]# ifconfig eth0 MTU 1500[[Email protected]~]# ifconfig eth0 eth0 Link encap:ethernet HWaddr00:0c:29:44:b7:60inet Addr:192.168.108.128 bcast:192.168.108.255 mask:255.255.255.0Inet6 addr:fe80::20c:29ff:fe44:b760/64scope:link up broadcast RUNNING multicast MTU:Metric:1RX Packets:399 errors:0 dropped:0 overruns:0 frame:0TX Packets:293 errors:0 dropped:0 overruns:0 carrier:0Collisions:0 txqueuelen:1000RX Bytes:39932 (38.9 KiB) TX bytes:38155 (37.2 KiB)

#route命令: For displaying and manipulating IP routing tables

Show current routing information:

[Email protected] ~]# Route

Kernel IP Routing tabledestination     Gateway         genmask         Flags Metric Ref use    Iface192.168.108.0   *               255.255.255.0   U     0      0        0 eth0192.168.122.0   *               255.255.255.0   U     0      0        0 virbr0

Brief description:

Destination: Target host or target network

Gateway Address (* indicates that the target is the network to which this host belongs and does not require routing)

Genmask: Network Mask

Flags Flag Description: U:up indicates that this route is currently in the boot state; H: Indicates that the target is the host; G: Indicates that the route is pointing to the gateway

Metric: Routing distance, number of relays required to reach the specified network (not used in the Linux kernel)

REF: Number of route entry references (not used in the Linux kernel)

Use: The number of times the route is used, which can roughly estimate network traffic to the specified network address

Iface: Output interface

Route-n: Use number format to display, do not reverse address to host name

Routes added to the host:

[[email protected] ~]# Route add-host 192.168.107.1 GW 192.168.108.25~]# route-nkernel IP Routing Tabledest Ination     Gateway         genmask         Flags Metric Ref use    Iface192.168.107.1   192.168.108.25  255.255.255.255 UGH   0      0        0 eth0192.168.108.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 Virbr0

Routes added to the network:

Route add-net 10.20.30.48 netmask 255.255.255.0 GW 10.20.30.41

Route add-net 10.20.30.48/24 GW 10.20.30.41

Add to Default route

default GW 192.168.1.55192.168.107.1   192.168.108.25  255.255.255.255 UGH   0      0        0  Eth0192.168.108.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr00.0.0.0         192.168.108.55  0.0.0.0         UG    0      0        0 eth0

Route del: Delete route

Remove a route to the host

[Email protected] ~]# route-nkernel IP Routing tabledestination Gateway genmask Flags Metric Ref use Iface192.168.107.1 192.168.108.25 255.255.255.255 UGH 0 0 0eth0192.168.108.0 0.0.0.0 255.255.255.0 U 0 0 0eth0192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0virbr00.0.0.0 192.168.108.55 0.0.0.0 UG 0 0 0Eth0[[email protected]~]# Route Del-host 192.168.107.1[[Email protected]~]# Route-nkernel IP Routing tabledestination Gateway genmask Flags Metric Ref use Iface192.168.108.0 0.0.0.0 255.255.255.0 U 0 0 0eth0192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0virbr00.0.0.0 192.168.108.55 0.0.0.0 UG 0 0 0 eth0

Remove routes to the network

Route Del–net 192.168.1.1

Remove to default route

 [[email protected] ~]# route-nkernel IP routing tabledestination Gateway        Genmask Flags Metric Ref use Iface  192.168.108.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0  192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0 virbr0  0.0.0.0 192.168.108.55 0.0.0.0 UG 0 0 0 eth0[[email protected]  ~]# route del default  [[email protected]  ~]# route-nkernel IP Routing TableDestination Gateway genmask Flags Metric Ref use Iface  192.168.108.0 0.0.0.0 2 55.255.255.0 U 0 0 0 eth0  192.168.122.0 0.0.0.0 255.255.255 .0 U 0 0 0 virbr0 
 

#配置DNS

[Email protected] ~]# vim/etc/192.168.108.1

Linux Learning Commands Summary ⑩⑥